code: def _find_executable(executable, path=None):
      """Tries to find 'executable' in the directories listed in 'path'.
  
      A string listing directories separated by 'os.pathsep'; defaults to
      os.environ['PATH'].  Returns the complete filename or None if not found.
      """
      if path is None:
          path = os.environ["PATH"]
  
      paths = path.split(os.pathsep)
      base, ext = os.path.splitext(executable)
  
      if (sys.platform == "win32" or os.name == "os2") and (
          ext != ".exe"
      ):
          executable = executable + ".exe"
  
      if not os.path.isfile(executable):
          for p in paths:
              f = os.path.join(p, executable)
              if os.path.isfile(f):
                  # the file exists, we have a shot at spawn working
                  return f
          return None
      else:
          return executable
  
file_path: catboost/contrib/tools/python/src/Lib/_osx_support.py
imports: import os
  import re
  import sys
label_desc: Use image node_id 1 for calling a global function with example usage: _find_executable(executable, path) and returns: None, executable, f